Our estimates show a pandemic with Rt values estimated mainly to remain below 1. We can now confirm that this fall in transmission has percolated through to the deaths, with the number of deaths occurring daily having peaked in the first week of November.
Plots of the IFR over time show that from the end of January we estimate a decreasing IFR in all adult age groups, but most steeply in the older ages. This drop indicates the benefits of immunisation against death over and above the benefits against infection. Following this drop, there has been a period of plateau followed by a gradual increase in the overall IFR to 0.3% (0.29%–0.31%). However, the age-specific IFRs appear to be falling, suggesting that the overall increase is due to shifting age patterns towards older people being infected. The estimated IFR is highest in the over-75s at 3.4% (3.3%–3.7%)
For context, in addition to the data used here, the number of reported new positive cases (by date of specimen) is very slightly increasing. As a caveat to this, trends in the number of reported cases are highly dependent on the volume and targeting of testing, the public’s testing behaviour and significant reporting delays, and therefore are difficult to interpret. Overall, there have been 8.7million positive tests, which, compared to our estimate of cumulative incidence, would suggest that, overall, around 1 in 3 infections have been identified. This seems plausible, particularly when considering the low ascertainment rates of the first wave. Admissions to hospitals have been falling in number, and the prevalence of infection, as estimated by the ONS Coronavirus Infection Survey, remains stable around 1.6% in England, while showing some slight increasing trends in some regions.
Real-time tracking of an epidemic, as data accumulate over time, is an essential component of a public health response to a new outbreak. A team of statistical modellers at the MRC Biostatistics Unit (BSU), University of Cambridge, are working to provide regular now-casts and forecasts of COVID-19 infections and deaths. This information feeds directly to the SAGE sub-group, Scientific Pandemic Influenza sub-group on Modelling (SPI-M), and to regional Public Health England (PHE) teams.
We fit a transmission model (Birrell et al. 2020) to a number of data sources (see ‘Data Sources’), to reconstruct the number of new COVID-19 infections over time in different age groups and NHS regions, estimate a measure of ongoing transmission and predict the number of new COVID-19 deaths.
We use:
Data are stratified into eight age groups: <1, 1-4, 5-14, 15-24, 25-44, 45-64, 65-74, 75+, and the NHS England regions (North East and Yorkshire, North West, Midlands, East of England, London, South East, South West).
Value of \(R_t\), the average number of secondary infections due to a typical infection today.
The percentage of a given group that has been infected.
NB: negative growth rates are rates of decline. Values are daily changes.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | -0.01 | -0.02 | 0.00 |
| East of England | -0.02 | -0.04 | 0.00 |
| East Midlands | -0.01 | -0.02 | 0.01 |
| London | 0.00 | -0.02 | 0.01 |
| North East | 0.00 | -0.02 | 0.02 |
| North West | -0.01 | -0.03 | 0.01 |
| South East | 0.00 | -0.02 | 0.01 |
| South West | -0.02 | -0.05 | -0.01 |
| West Midlands | -0.02 | -0.04 | 0.00 |
| Yorkshire and The Humber | -0.03 | -0.05 | -0.01 |
Halving times in days, if a region shows growth than value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 75.55 | 44.71 | 248.83 |
| East of England | 35.02 | 16.85 | 267.39 |
| East Midlands | 81.69 | 28.02 | NA |
| London | 181.94 | 37.32 | NA |
| North East | NA | 39.63 | NA |
| North West | 65.44 | 22.15 | NA |
| South East | 633.62 | 42.37 | NA |
| South West | 28.53 | 13.51 | 94.13 |
| West Midlands | 30.79 | 16.50 | 271.94 |
| Yorkshire and The Humber | 21.00 | 12.48 | 49.10 |
Doubling times in days, if a region shows decline then the value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | NA | NA | NA |
| East of England | NA | NA | NA |
| East Midlands | NA | 93.80 | NA |
| London | NA | 58.75 | NA |
| North East | 462.67 | 36.51 | NA |
| North West | NA | 92.72 | NA |
| South East | NA | 54.24 | NA |
| South West | NA | NA | NA |
| West Midlands | NA | NA | NA |
| Yorkshire and The Humber | NA | NA | NA |
NB: negative growth rates are rates of decline. Values are daily changes.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 0.00 | 0.00 | 0.01 |
| East of England | 0.00 | -0.02 | 0.01 |
| East Midlands | 0.01 | 0.00 | 0.02 |
| London | 0.00 | -0.01 | 0.02 |
| North East | 0.02 | 0.00 | 0.03 |
| North West | 0.00 | -0.02 | 0.01 |
| South East | 0.01 | -0.01 | 0.02 |
| South West | -0.01 | -0.03 | 0.00 |
| West Midlands | -0.01 | -0.02 | 0.01 |
| Yorkshire and The Humber | -0.02 | -0.03 | 0.00 |
Halving times in days, if a region shows growth than value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | NA | 158.38 | NA |
| East of England | 176.42 | 39.30 | NA |
| East Midlands | NA | 226.38 | NA |
| London | NA | 79.34 | NA |
| North East | NA | NA | NA |
| North West | 206.81 | 41.13 | NA |
| South East | NA | 94.91 | NA |
| South West | 62.31 | 26.71 | NA |
| West Midlands | 96.04 | 35.67 | NA |
| Yorkshire and The Humber | 40.44 | 24.08 | 218.24 |
Doubling times in days, if a region shows decline then the value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 1515.13 | 127.95 | NA |
| East of England | NA | 66.42 | NA |
| East Midlands | 71.52 | 28.89 | NA |
| London | 200.27 | 40.20 | NA |
| North East | 42.01 | 20.12 | 1393.72 |
| North West | NA | 59.94 | NA |
| South East | 122.57 | 35.21 | NA |
| South West | NA | 330.47 | NA |
| West Midlands | NA | 80.09 | NA |
| Yorkshire and The Humber | NA | NA | NA |
## The execution of the prevalence code block will proceed if
## prev.dat exists and this is TRUE
## it is not and external report and this is FALSEThe shaded areas show periods of national lockdown, the green lines the dates (once confirmed) of the steps in the roadmap in the UK Governement’s COVID-19 Response – Spring 2021, and the red line shows the date these results were produced (26 Nov).